Porsche Restoration Project: Air Conditioning
Griffiths Technical Inc. was tasked with reinstalling the air conditioning in this RHD (right hand drive) 1974 Porsche Turbo. This early prototype turbo is being fully restored by Dawes Motorsports in Stroudsburg, PA. Peter Dawe is well-known in the Porsche racing community for his engine work and restoration projects. Most of the original air conditioning components were supplied by Dawes, while Griffiths provided installation, minor modification improvements, and AC technical support.
Jesse Griffiths assisted throughout this project. He has a unique talent to quickly assess a situation, develop solutions, and implement them.
The early 930 utilized a 10 cu.in. York orientated horizontally on its side, similar to the early 911’s.
Deck Lid Condenser
One condenser was mounted in the engine deck lid, toward the end of the wing. It’s roughly the size of a typical 911 or 930 front condenser.
The deck lid condenser has a unique fiberglass cooling shroud which increases air flow pulled directly by engine cooling fan and averts warming the air consumed by the engine through the air filter. Connecting the refrigerant lines to the deck lid condenser is a 2 person task, as you need to pre-attach the hoses and mount the unit into the deck lid with an underside fascia pan.
The front condenser is similar to a typical 911/930 both in size and mounting location. The unit is protected by 911/930 style perforated metal stone guard. A blower fan alike the 911/930 is mounted in the front trunk and pulls air from behind the bumper and moves it downward over the condenser. Throughout the project, we were consistently amazed at the fine details put into this classic 930 by Dawes Motorsports.
Evaporator, Blower Motor & Fan Speed Controller
Since this is RHD, the evaporator/blower box is mounted inside the cockpit at the LH side foot board area. Air from the box is moved through a “Y’ connection pipe to individual knee pad vent panels, which contain the thermostat and evaporator fan speed control.
RHD evaporators require a downward-mounted condensation drain funnel. Not seen in this evaporator box was an upgraded Kuehl Hurricane Evaporator Blower Motor which will put out 30% more air volume. Hidden behind the evaporator box are the AC electronics, including a Kuehl Variable Speed Fan Controller, allowing the driver to have full variable speeds.
AC Refrigerant Hoses
The early cars used conventional non-barrier hoses covered in red braided fabric with Aeroquip style connectors. Production of that style of hose was discontinued years ago, so we used modern barrier hoses. Barrier hoses have a very low permeability rate, leading to a significant retention of refrigerant (as compared to most 911/930’s using old style refrigerant hose). We covered each hose with a special braided fiber wrap to give the car a bit of the retro look. As an added benefit, the hoses are now more resistant to abrasion, chemicals and heat.
We will continue updating this article with pictures and info as the project progresses.